A model of the bolt catch inserts for Ghost Gunner's AR-00 Zero Percent Receiver project. These inserts slot into holes milled into the upper lower. They are used to hold the bolt catch in place, in lieu of a more complicated milling procedure to mill this into the upper lower itself.
Ghost Gunner sells these printed in nylon. Other materials might also be acceptable for these inserts, but Ghost Gunner has not tested these.
The bolt catch inserts can be purchased as part of the Ghost Gunner Zero Percent Lower Build Kit at https://ghostgunner.net/product/zero-build-kit/.
Learn more about the Ghost Gunner Zero Percent Receiver at zero.ghostgunner.net.